I wasn't sure what screws I was supposed to use to secure my motherboard (they all came in one little baggie) and I used the some of the extras that are supposed to be used to secure the back plates in. Will this effect my motherboard at all? Or should I swap them out while I have the chance?
^ DO NOT USE any that have 'ridges' under the screw head! -- SMOOTH ONLY.
Over the years, both 6-32 and M-3 threads have been used for MoBo standoffs. The 6-32 is a coarse thread and is also what is generally used to hold power supplies, expansion cards and case covers in place. Look at the gallery at bottom of page on the wiki link below and you'll see a close-up of a 6-32 screw with a hex cap / Phillips head.
Each standoff has a "male" portion that screws into the case, and a "female" portion that receives a screw that has passed through a specially grounded pre-drilled hole in the motherboard. Standoffs that use strictly M3, strictly 6-32, or a combination (male portion 6-32, female portion M3) are all fairly common.
The problem is when someone .....
6-32 screws will fit into holes threaded for M3 screws (the second most common type of screw in PCs), but this will damage the finer M3 threading. Also, when 6-32 screws are screwed into brass M3-threaded motherboard standoffs, the threads tend to become "locked", and the entire motherboard must be removed to separate them.
Built 3 PC's this week, starting another one in about an hour .... four sets of screws "in each box":
1. Thumbscrews, obviously not for MoBo (Top in photo) - 4 provided
2. Brass standoffs (2nd from top, left) - 10 provided
3. Hex head coarse 6-32 thread screws with very slight ridges on underside (3rd from top, right) - 10 provided and they fit standoffs
4. Component screws, fine M-3 thread, dome heads for optical drives DVD-ROM's (bottom) - 8 provided (one short if they are for MoBo) and these do NOT fit brass standoffs. Screws go in just 1 turns and then become "wedged"
In short, before ya start ya work, open the bag of screws and test hand tightening the screws into the standoffs. It's a sure bet that only one type will screw in to a depth that is appropriate for the MoBo. If it doesn't screw in easily with just light grip w/ 2 fingers, ya got the wrong screw.